| Rahn-Otis sample | An approximation of alveolar gas continuously provided by a simple device that admits just the latter part of each expiration. (05 Mar 2000) |
|---|---|
| random sample | A group selected randomly, solely by chance. (12 Dec 1998) |
| Haldane-Priestley sample | <physiology> An approximation of alveolar gas obtained from the end of a sudden maximal expiration into a Haldane tube. (05 Mar 2000) |
| probability sample | Each individual in the sample has a known, generally equal, chance of being selected. (05 Mar 2000) |
| sample | 1. A specimen of a whole entity small enough to involve no threat or damage to the whole; an aliquot. 2. A selected subset of a population; a sample may be random or nonrandom (haphazard); representative or nonrepresentative. Origin: M.E. Ensample, fr. L. Exemplum, example (05 Mar 2000) |
| sample, random | A group selected randomly, solely by chance. (12 Dec 1998) |
| sample size | The number of units (persons, animals, patients, specified circumstances, etc.) in a population to be studied. The sample size should be big enough to have a high likelihood of detecting a true difference between two groups. (12 Dec 1998) |
| stratified sample | A subset of a total population, defined by some objective criterion such as age or occupation, is sampled. (05 Mar 2000) |
| end-tidal sample | A sample of the last gas expired in a normal expiration, ideally consisting only of alveolar gas. (05 Mar 2000) |
| atomic volume | The atomic weight of an element divided by its density in the solid state; the volume of the gram-atomic weight of a solid element. (05 Mar 2000) |
| blood volume | Volume of circulating blood. It is the sum of the plasma volume and erythrocyte volume. (12 Dec 1998) |
| blood volume determination | Method for determining the circulating blood volume by introducing a known quantity of foreign substance into the blood and determining its concentration some minutes later when thorough mixing has occurred. From these two values the blood volume can be calculated by dividing the quantity of injected material by its concentration in the blood at the time of uniform mixing. Generally expressed as cubic centimeters or liters per kilogram of body weight. (12 Dec 1998) |
| blood volume nomogram | A nomogram used to predict blood volume on the basis of the individual's weight and height. (05 Mar 2000) |
| cardiac volume | The volume of the heart, usually relating to the volume of blood contained within it at various periods of the cardiac cycle. The amount of blood ejected from a ventricle at each beat is stroke volume. (12 Dec 1998) |
| packed cell volume | <haematology> Measurement of the proportion of the blood occupied by the red blood cells. Normal values are 40-54% in males, 35-47% in females. (13 Nov 1997) |